The present invention relates to an air filter which is to be used in an air conditioning apparatus or the like installed in a building or the like.
In an air-conditioning air filter of this type, conventionally, a main box in which an air inlet is opened in one side and an air outlet is opened in the opposite side is produced, and filter elements are arranged in a zigzag manner between the air inlet and the air outlet in the main box, and integrally bonded with an adhesive agent. Recently, instead of the configuration in which only filter elements are directly bonded in the main box, a configuration is employed in which a plurality of filter bodies in each of which the outer circumference of a filter element is surrounded by a filter frame are produced, and the plurality of filter bodies are arranged in a zigzag manner in the main box.
As for the former air-conditioning air filter in which the filter elements are integrally bonded to the main box in an inseparable manner, however, the air filter is thrown away after only one use. In other words, the air filter is of a disposal type. This results in an increase of garbage, and this is extremely uneconomical.
As in the latter air filter, when filter bodies in each of which the outer circumference is surrounded by the filter frame are produced and the filter bodies are accommodated and disposed in the main box in a detachable manner, the main box and the filter bodies can be separated from one other. Therefore, washing or replacement of only the filter body can be performed, so as to realize a saving in resources and a decrease in garbage.
In this case, however, the main box is configured by a plastic molded product, and often molded so as to be relatively thin for the purposes of reducing the weight and the materials. In this case, when the main box receives a positive pressure or a negative pressure due to the air flowing in the main box, the main box is easily flexurally deformed. In the case where filter bodies are extractably accommodated in such a plastic main box in a sliding manner, a gap is produced between slide faces formed by inner faces of a top plate and a bottom plate of the main box and upper and lower end portions of the filter bodies, in conjunction with the flexural deformation in which the main box is swelled outward due to the positive pressure. This produces a problem in that the air may leak out through the portion without being filtered.
It is an object of the invention to provide an air-conditioning air filter in which cleaning or washing, or replacement of only a filter body configured by a filter element and a filter frame can be performed, so as to realize the saving in resources, the reduction in garbage, and the reduction in cost. It is an another object of the invention to provide an air-conditioning air filter in which air leakage between slide faces formed by inner faces of a main box and upper and lower end portions of filter bodies can be prevented from occurring.
The air-conditioning air filter of the present invention comprises: a main box made of plastics and having a shape in which an air inlet is opened in a front side and an air outlet is opened in a back side, an upper side is closed by a top plate, a bottom side is closed by a bottom plate, and right and left sides are closed by right and left side plates, respectively; and a plurality of filter bodies which are extractably accommodated in a zigzag manner between the air inlet and the air outlet in the main box, and each of the filter bodies is formed by fitting a bellow-like filter element into a rectangular filter frame. In such an air-conditioning air filter, sliding channels are formed in upper end faces and lower end faces of the filter frames, respectively, over a whole length in anteroposterior direction, and right and left guard rails having a shape which covers both sides of the upper end faces and the lower end faces of the filter frames, and guide rails which are placed in parallel with and between the right and left guard rails and to be slidably fitted with the sliding channels are protrudingly formed in a zigzag manner on inner faces of the top plate and the bottom plate of the main box, respectively. Engaging projections are protrudingly and horizontally disposed on inner sides of the right and left guard rails, and engaging channels which are to be slidably engaged with the engaging projections are disposed over a whole length in anteroposterior direction on both side faces of the upper end portion and the lower end portion of the filter frame in each of the filter bodies.
According to the thus configured air-conditioning air filter, since the filter bodies are extractably accommodated in the main box, the filter bodies can be taken out of the main box, and can be easily cleaned or washed, or replaced, so that the filter bodies can be reused. In addition, the filter bodies can slide by means of the upper and lower sliding channels along the guide rails between the upper and lower guard rails of the main box. Therefore, the filter bodies can be smoothly inserted into and extracted from the main box in anteroposterior direction without disengaging the sliding channels from the guide rails. In the filter bodies, the upper and lower engaging channels are slidably engaged with the engaging projections of the main box. Even in the case where the main box is flexurally deformed by a positive pressure to be swelled outward, the top plate and the bottom plate of the main box can be prevented from separating from the upper and lower end faces of the filter bodies, by the engagement function between the engaging projections and the engaging channels. Accordingly, it is possible to prevent a gap from being produced between the sliding faces of the upper and lower guide rails of the main box and the upper and lower sliding channels of the filter bodies, so that the air can be prevented from leaking out through the portion without being filtered.
The air-conditioning air filter of the invention comprises: a main box made of plastics and having a shape in which an air inlet is opened in a front side and an air outlet is opened in a back side, an upper side is closed by a top plate, a bottom side is closed by a bottom plate, and right and left sides are closed by right and left side plates, respectively; and a plurality of filter bodies which are extractably accommodated in a zigzag manner between the air inlet and the air outlet in the main box, and each of the filter bodies is formed by fitting a bellow-like filter element into a rectangular filter frame, wherein sliding channels having a T-shaped section are disposed on one of a pair of inner faces of the top plate and the bottom plate of the main box and a pair of an upper frame and a lower frame of each of the filter frames, and guide rails having a T-shaped section with which the sliding channels are to be fitted are disposed on the other pair.
According to the thus configured air-conditioning air filter also, since the filter bodies are extractably accommodated in the main box, the filter bodies can be taken out of the main box, and can be easily cleaned or washed, or replaced, so that the filter bodies can be used again. The filter bodies can be smoothly inserted into and extracted from the main box without derailing, by causing the upper and lower sliding channels having the T-shaped section to slide along the upper and lower guide rails having the T-shaped section. At the same time, even in the case where the main box is flexurally deformed by a positive pressure to be swelled outward, it is possible to prevent a gap from being produced between the sliding faces of the guide rails and the sliding channels, so that the air can be prevented from leaking out through the portion.